CZ281093A3 - Eye lens carrying device - Google Patents

Abstract

An apparatus for carrying an ophthalmic lens, particularly while the lens is being inspected, including a base member and a well connected to the base member. The well is substantially transparent, and includes a frusto-conical sidewall having a constant slope, and a hemi-spherically shaped bottom portion connected to an extending downward from the sidewall. The bottom portion of the well has curvature that is about 10% larger than the radius of curvature of the ophthalmic lens. <IMAGE>

Description

The invention generally relates to carriers, ophthalmic lenses, in particular ophthalmic lens carriers, which are very suitable for holding contact lenses while inspecting them.

BACKGROUND OF THE INVENTION

Typical for contact lenses is that they are manufactured with a high degree of accuracy. However, in rare cases i. They may experience some inaccuracies and for this reason contact lenses are inspected before they reach the consumer to determine if the contact lenses are actually acceptable to the consumer.

One type of known control system is a system in which the lenses are placed in small wells or pans and move with them through the lens inspection position, with the illumination rays passing through the individual lenses. The illumination beams are then focused on the screen where. create an image of the lens, and by looking at the image, the operator determines whether the lens contains any inaccuracies. If any defect or defect is detected, the produced lens is not consumer-friendly and is directly removed from the inspection system or labeled in any way and consequently does not reach the consumer.

The lens carrier is an important element of this inspection system. In particular, it is important to minimize the effect that the lens carrier has on the beam of light rays passing through the ophthalmic lenses, which causes the defects arising in that beam of the lens carrier to control a controlled lens.

rays caused by said operator to be considered defects in

Furthermore it is very advantageous if the removable lens carrier easily, whereas that with repeated use and ^one lens carrier may cause a 'damage caused by scratches and scratches may deflect or refract part of the illuminating beam used to control the ophthalmic lens. The operator can observe the image produced by the refracted or deflected light and consider it a defect or a defect in the inspected lens.

In spite of the above, the known control systems of the general type described above are very efficient and reliable, but on the other hand, they must be said to be quite slow and costly, since the operator has to sharpen the image of the lens formed on the screen and check for any caries. It is believed that the known systems can be improved and, in particular, the financial cost of. the lens control is reduced and the speed of the control is increased by the introduction of an automated control system.

In any automated system, it is important that the lens be positioned precisely with respect to the translucent beam passing through the controlled lens, which in turn requires the lens carrier to meet the requirements of the lens. the criteria described above, to hold the lens in a precisely defined position as it moves through said system, and to be movable about a predetermined path ......

SUMMARY OF THE INVENTION

It is an object of the invention to improve ophthalmic lens carriers.

It is a further object of the invention to provide a disposable lens carrier which is particularly suitable for accommodating the holding and displacement of contact lenses in an automated lens inspection system.

member

Each comprising a base member.

Another object of the invention is to provide a lens carrier having a plurality of lens-shaped dishes; with each dish the contact lens is placed in a specific, precisely defined position within the dish and held thereafter in the dish.

These and other objects are achieved by an ophthalmic lens support device, the plurality of wells attached to the wells being substantially transparent and adapted to hold the respective lens. Each of these wells further comprises a frustoconical side wall having a constant slope and a hemispherically shaped bottom attached to a downwardly extending side wall. The bottom of each well has a constant radius of curvature about 10% greater than the radius of curvature of the co-located in said well.

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Preferably, the side wall of each well extends at an angle of about 20 ° from the axis of said well and the thickness of the side wall of each well is less than about 0.25 mm. In addition, preferably the bottom of each well has a diameter greater than the diameter of the lens located in the well, and each well also has a depth greater than the diameter of said lens.

Further successes and advantages of the invention will become more apparent from the following detailed description and accompanying drawings which specify and illustrate preferred embodiments of the invention. *

Brief description of the pictures

Fig. 1 schematically illustrates an automatic lens inspection system.

Fig. 2 is a plan view of one type of ophthalmic lens in which inspection can be performed using the system shown in Fig. 1; Fig. 3 shows an enlarged view of the peripheral portion of the lens shown in Figs. 2 and 3; Fig. 4 shows a much more detailed view of Fig. 2; a view of the transport subsystem used in the control system shown in Figure 1;

Figure 5 is a plan view of the lens carrier used in the system shown in Figure 1; Figure 6 is a side view of the lens carrier shown in Figure 1; Figure 7 is a schematic diagram generally illustrating the principles of imaging technology referred to as -light-l-illumination. dark ^- pďel ''^'1''Figure 8 depicts a more detailed diagram of the illumination and imaging subsystems of the lens inspection z.názornenénc to oorázku ^1, Figure 9 shows a portion of the pixel array of the display subsystem 10 shows an image that is formed naaesku- pixel frothing when the optical lens of the type shown in Figures 2 and 3 is inspected in the inspection system shown in Figure 1, Figs. 11A, 11B and 11C illustrate three alternative optical configurations that may be used in the lighting and display subsystem; control subsystem of the control system Fig. 12b is a timing diagram illustrating a sequence of various phenomena in the operation of the transport, lighting and imaging subsystem; Fig. 13 schematically illustrates a data processing subsystem of the lens inspection system; lens system - ¹ ··

Fig. 15 is an image of an ophthalmic lens formed on a pixel grouping of the lens control system; Figs. 16A and 16B illustrate flowcharts illustrating a lens inspection process designated as a decentralization test; oor. ί iu shows the invite!

17A, 17C is a graph showing the intensities at which certain pixels in the linear segment shown in FIG. 17B are illuminated, FIGS. 17D-17I graphically illustrate the results of various procedures performed at light intensity values of certain pixels to 17A, 17J illustrates pixel-spaced pixels illuminated at their operational illumination values; FIG. 18 is a flowchart of a preferred process for processing the input illumination intensity values determined for the pixels. Figs. 19A-19C. show the effect of the masking process on data values for pixels of the pixel array; Fig. 20 is a flowchart illustrating a preferred masking process; Figs. 21A and 21B illustrate another process for processing data denoted as an allegorite. 22 shows a subroutine used to identify the first pixel at the edge of a linear image, FIG. 2 shows an evolutionarydiagram with respect to _. Fig. 24 shows a flowchart showing below the program that is used when a gap is found on the outside of the edge of said lens image; Figs. 25A-25S show a portion of the outside edge of said lens image and identify different pixels on that edge Fig. 26 shows a flowchart of a subroutine that is used when a domed portion is found at the outer edge of the lens image; Fig. 27 is a program that is used after the procedure outlined in Figs. 23 terminated,

Fig. 28 shows a portion of the flowchart that deals in more detail with the second major portion of the elastic band algorithm; Fig. 29 shows a portion of the outer edge of the lens image and several vectors that are used in the second portion of the elastic band algorithm. 31 and 32 illustrate the effect of the two steps of the procedure shown in FIG. 30, FIG. 33 illustrates a portion of the outer edge of the ring, with respective lines attached thereto, FIGS. 34A to 34E generally illustrate results of various operations labeled as MAX, PMAX, MIN and PMIN, Fig.35 illustrates a preferred procedure that applies pixel data to emphasize possible edge defects

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v. i is. Fig. 36 shows the results of the process shown in Fig. 35; 38A to 38C illustrate illustrating the second masking process and its results, _% t Fig. 39 shows a flowchart of another process applied to pixel data to emphasize other possible defects 40A to 40D illustrate the individual operations and results of the procedure outlined in FIG. 39, FIG. 4! A and 41B show a flow chart of a procedure used to identify any defects or defects in a lens being inspected. FIG. 42 shows the different types of defects that may occur with the lens.

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The block diagram shown in Figure 1 illustrates a lens inspection system 10, the system 10 generally including a transport subsystem 12, a lighting system 14, an imaging subsystem 16, and an image processing subsystem 20. In a preferred embodiment of the system 10, the transport subsystem 12 includes a lens carrier 22 and a support assembly. 24 (shown in FIG. 4), the illumination system 14 includes a housing 26, a light source 30 and a mirror 32 and 34, the display subsystem 16 including a camera 36, a housing 40 and a lens assembly 42. In more detail (FIG. 8) 36 includes a housing 44, a pixel array 46 and a lens 50, and the lens assembly 42 includes a housing 52, a pair of lenses 54 and 56 and a plurality of reflector plates 60. The image processing subsystem 20 includes a forward processor 62, a main processor 64 and input means such as a keyboard 66 wherein preferably the subsystem 20 '. further comprising a memory unit 70, a display monitor 72, a keyboard terminal 74, and a printer 76.

Generally, it is the task of the transport subsystem 12 to convey a plurality of ophthalmic lenses along a predetermined path and to transport one of the lenses at a particular point in time to the position of the lens itself (the control position), one such lens 80 in the control position. 1 shows FIG. The task of the lighting subsystem 14 is to generate a series of light pulses and to direct the individual light pulses along the light path 82 through the individual eye lenses passing through the control position. Subsystem 16 generates a set of signals representing selective portions of the light pulses transmitting the ophthalmic signals to the processing sub-processing subsystem 20 to receive them through the lens, and then to the system 20. The image of the ruriases with oscillation;

a predetermined program to determine if at least one condition is met for each of the lenses being inspected, and in a preferred embodiment of subsystem 20, which will be forwarded in greater detail10, the subsystem 20 determines whether the individual lenses suitable for consumer use.

The system 10 can be used to control very different types and sizes of ophthalmic lenses. The system is particularly suitable for inspecting contact lenses (Figures 2 and 3, for example, show a contact lens 84 that can be inspected by system 10). the lens 84 is generally hemispherical in shape, including front and rear surfaces 86 and 90, ^and is formed by a central optical zone 84a and an outer zone 84b. the lens has a substantially uniform width, however, as shown in particular in Figure 3A, the thickness of the lens is on. Rings .84c the middle edge of the outer edge gradually decreases.

Figure 4 shows in more detail the transport subsystem 12, which, as already mentioned, preferably comprises a lens carrier 22 and a carrier assembly 24. More specifically, the support assembly 24 includes a translation plate 92 and first and second stepping motors 94 and 94, respectively. 96, wherein the translation plate 92 in turn comprises a base member 100 and frames 102 and 104.

The objective of the lens carrier 22 is generally to retain a plurality of optical lenses (Figures 5 and 6 illustrate the lens carrier 22 in more detail). The lens carrier 22 includes a rectangular base member 106 and a plurality of lens-shaped inspection trays 110 attached to the base member 106. Each dish 110 is preferably formed by a body or a skin. 11-1 integrally connected to the side wall of said cup and extends downwardly therefrom. In addition, the bottom of each cup preferably has a constant radius of curvature, which is approximately 10 times greater than the radius of curvature of the optical lens 3 * disposed in said cup, and the diameter of the bottom 110b is greater than the diameter of said ophthalmic lens. Further, the side wall 110a of each cup extends at an inclination of about 20 ° relative to the axis of said cup, and the thickness of each side wall is preferably less than about 0.254 mm.

Specifically, with respect to the lens carrier 22 shown in Figures 5 and 6, the upper diameter of each dish 110 is about 22 mm and the depth of each dish 110 is preferably greater than the diameter of the lens to be inspected, this diameter being for constant lenses usually 20 mm. As shown in FIGS. 5 and 6, the lens carrier 22 is typically formed by a group of 3x4 control dishes (3 rows of 4 dishes). However, it will be appreciated that the control dishes may be arranged in other ways, for example they may be arranged in a 3x3, 3x8, 4 x 8, 3 χ 10 or 4x10 grouping.

The trays 110 and preferably the base member 106 are made of a substantially transparent material such as polivinyl chloride plastic material. In addition, the trays 110 and base member 106 are preferably formed together to form a single compact unit and their thickness is relatively small, thereby reducing cost, which in practice allows the lens carrier 22 to be used once. remove (disposable carrier). Removing said carrier. 22 significantly reduces or completely eliminates the formation of scratches on the trays after single use, which often occurs when the control trays 110 are used repeatedly. Because, as will be discussed below, scratches on the tray may be considered as ^! lens defects located within said cup, the use of easily removable lens carriers 22 improves the accuracy of lens inspection.

In use, each cup 110 is partially filled with a liquid solution 112, such as saline solution, and one bottom of each cup is fitted with one fitting ophthalmic lens so that it is completely immersed in the solution contained in the cup. After placing the lens in the dish 110, due to the shape and other parameters of the dish 110 described above, the dish 110 tends to automatically center the lens at the bottom of the dish.

Referring still to Figure 4, the task of the support assembly 24 is to fix the lens carrier 22 and move it so that all the lenses contained therein are transported one after the other to the position in which they will be inspected (hereinafter referred to as the inspection positions). Preferably, the support assembly 24 moves the lens carrier 22 continuously along a predetermined path in order to convey the lenses 84 continuously to and through said control position. The support assembly can be, for example, such that when the lens carrier 22 is moved, it passes through the control position. first one row of trays 10 of carrier 22, then the support assembly 24 moves the carrier 22 so that another row of trays 10 of carrier 22 aligns with the control position and then passes the trays 11 provided in the tray. this control position. (Of the preferred support assembly 24 shown in FIG. 4, the frame 102 of the translation plate 92, which is intended for lateral movement to the right and left, is supported by the base 100, as shown in FIG. the up and down movement (see FIG. 4) is supported by the frame 102, and the lens carrier 22 is supported by the frame 104. The stepper motor 94 is fixed to the base 100 and coupled to the frame 102 and is intended to move the frame across the base member 100. The stepper motor 96 is in turn mounted to the frame 102 and coupled to the frame 104 to move the frame 104.

Any suitable frames 102 and 104 and stepping motors 94 and 96 may be used with the support assembly 24. In addition, it will be appreciated that for the movement of the lens support 22 in a desired manner, another known support assembly is known.

Still with respect to Figure 1, subsystems 14 a. 16 ,. together they produce and then utilize a phenomenon referred to as dark field illumination to control ophthalmic lenses moving through the control position. In this procedure, an image on a 46-pixel array is formed by some features of an optical lens that scatter or refract light transmitted through the lens. Darkfield illumination can be used to detect blemishes and irregularities in optical lenses, and since virtually all defects, as well as some normal features of optical lenses, scatter light, and using this dark field illumination procedure, which is truly a highly efficient procedure, even slight surface defects that are too deep can be detected.

The principle of dark field illumination can be understood from Figure 7, which illustrates the optical lens 114, the collimated light beam 116, the pair of lenses 120 and 122, the opaque cap 124, and the array of 126 pixels. The beam 116 of light rays passes through the ophthalmic lens 114 and then impinges on the imaging lens 120. If the beams of the illumination beam 116 have been precisely collimated, they should collide at the rear focus point of the lens 120 Also, if the light beam 1116 is not completely affected by the ophthalmic lens 1114, although the beam 116 is not exactly collimated on impact on the lens 120, the beam 116 forms a small circle at approximately the rear focus of the lens 120, referred to as the least irregularity circle. . The cap 124 is located on the other side of the imaging lens 120, at the aforementioned rear focus of the lens, the size of the cap 124 being chosen to slightly overlap the circular image formed by the beam 116 of the illumination at the rear focus of the lens 120.

So if there is no scattering or refraction of the illumination beam, the face of the rays that is ^; · Caused by cy.lwu 114, no light will pass through the cap 12 4 and the array of 12 6 pixels will remain completely dark. However, any feature of the lens 114 that refracts light by passing said cap 124 causes a portion of the light to strike the array of 126 pixels. The ophthalmic lens 114 is positioned in a position optically coupled to the array position 126 pixels and thus, when any light passes beyond the cap 124, forms an image of the light diffuser feature on the array 126 pixels.

Figure 8 illustrates a preferred embodiment of a device producing and subsequently using the aforementioned dark field illumination phenomenon in the system 10, and in particular illustrates in more detail the preferred lighting subsystem 14 and the display subsystem 16. As can be seen from this figure, the subsystem 14 comprises a housing 26; mirrors 32 and 34, diaphragm 130 ·, - power source "132, control circuit 134 'The first and second adjustable support means' and 136 and 140' output window 14 of the second subsystem 16 further includes a camera 36, and ^Cr ytku assembly 42 lenses. More specifically, the camera 36 includes a housing

44, the array of 46 pixels and the lens 50, and the lens assembly 42. ..

it comprises a cover 52, lenses 54 and 56, and reflective plates 60.

The housing 26 of the subsystem 14 forms a protective housing for the other elements of the subsystem, wherein both the light source 30 and the mirrors 32 and 34 and the screen 130 are housed in the housing. More specifically, the cover 26 comprises a main vertical leg. 26a and upper and lower horizontal legs 26b and 26c, the light source 30 being disposed within the main leg 26a of the housing 26. The mirror 32 is secured to the junction of the leg 26a and the leg 26c, the mirror 34 is disposed at the distal end of the leg 26c and the customs. a_1_3-0_j.e ^ _um can stand on. The housing 26 further includes an opening 26d which is located directly above the mirror 21. The aperture 26d is secured by a window 142. In use, the light source 30 generates a plurality of light flashes, or i, i =; ύ, each of these pulses propagating along the light path 82. On this path 82 a mirror 32 is provided. which directs the light pulses through the aperture 130 to the mirror 21 / which in turn directs the light pulses upwardly through the window 142, through the lens placed in the control position (indicated by the reference numeral 114 in Figure 8) and towards or toward the display subsystem 16.

Preferably, the light source 30 is attached to an adjustable support means 136 that allows to set a specific direction of light emission emitted from the light source, and the mirror 34 is mounted to another adjustable support means 140 that allows to set both a specific light direction and a specific light direction. the position of refraction on the mirror. In a preferred embodiment of the subsystem 14 shown in FIG. 8, the support means 136 includes an evasion member that is secured to the housing 26 and is rotatable about two mutually orthogonal horizontal axes. In this embodiment of the subsystem 14, the mirror support means 140 further comprises an evasion member 140a and a slider 140b, wherein the mirrors 34 are mounted on the evasion member 14a, which in turn is attached to the slider 140b. The cell 14qb is movable laterally to the right and to the left (see Fig. 8) and allows to adjust the lateral position of said mirror 34, the cell 140a being rotatable about two mutually perpendicular horizontal axes to allow the specific angle of the mirror 34 to be adjusted.

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The display subsystem 16 receives light pulses passing through the ophthalmic lens located at control position 1-44 and generates a series of signals representing selected portions of light passed through the ophthalmic lenses. More specifically, the array of 46 pixels is located inside the camera housing 44, directly behind the lens 50, and is preferably comprised of a plurality of light sensors, each of which is capable of generating a corresponding electric current, the size of which corresponds to or represents light intensity incident on the sensor.

Figure 9 shows an enlarged view of a small portion of a 46 pixel array, in particular showing a plurality of individual 16 dual light sensors of said array of 46 pixels.

With respect to this figure, the light sensors or pixels are preferably arranged in a regular suture with a given number of rows and columns, for example the network may comprise one million pixels arranged in one thousand columns and one thousand rows. Preferably, in this network, the pixels form a plurality of uniformly spaced rows and a plurality of uniformly spaced columns, and in addition to those pixels that lie along the actual edge of said array, each pixel has eight immediate neighbors. For example, pixel 146a.a. has eight_s.o.u.s.e-d: pixel 146b lying directly, above it, pixel 146c located directly below it, pixels 14d, and 146e lying right, respectively. to his left. and pixels 146f, 146.g, h46h and 146i lying at the top and 'to the right respectively. and on the left and bottom and, on the right respectively. down and left. *

..... Yet, _k. .o.b.r.á.zku. 8 · ,. The cap 40-4 and the lenses 5-4 and 5-6 are advanced in front of the lens 50 and are coaxially aligned with the array of 46 pixels and the camera lens 50. The cap 40 is positioned between the lenses 54 and 56 substantially in the rear focal plane of the lens 54 and the lens 56 is positioned such that the array. 46 pixels lie in the rear focal plane of the lens 56. Preferably, the lens 54 and 56 and the cap 40 are mounted within the housing 52, which in turn is secured to the front end of the camera 36. In addition, reflective plates are preferably spaced along the entire length of the housing 52. 60, which may consist of a series of rectangular-shaped members, and which helps-if-can-with-the-air-to-the-air cover ~ 5 ~ 2 ~; - ~~

At this specific location, the lenses 54 and 56 and the cap 40 are all light rays, or at least most

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- .i ... j sJ L x j .. u -3 11 ς • ^ «ι τ '» «. ti 1 «i-». _v V Λ Ul ó · ιγ '' .U «X r. χ. Q. The lens to be inspected by the lens 54 is focused on the cap 40 and thus does not fall on a group of 46 pixels. However, a portion of the light passing through the irregularities of the ophthalmic lenses, as well as a portion of the light passing through the visible structure of some ophthalmic lenses, can be refracted to the extent that this light is then not focused on the cap 40 by the lens 54 but instead passes around the cap 40 and falls on a group of 46 pixels. In addition, the control position of the lenses is optically associated with the position of said array of 46 pixels, and thus any light that passes beyond the cap 40 will form an image of an ophthalmic lens feature that scattered the light onto the array of 46 pixels. ...

This process, referred to as dark field illumination, is a very effective way of illuminating irregularities of ophthalmic lenses, and Figure 10 shows an image formed on a group of 46 pixels by light rays that have passed through the ophthalmic lens, in particular a contact lens.

2a. Most of the light that passes through the lens is prevented from affecting the 46-pixel array by the cap 40. However, due to the uneven ring thickness ...

84c of the lens, the light passing through the lens portion refracts outside the cap 40 and impinges on the array of 46 pixels, wherein.

forms a ring image on this grouping 46. Irregularity- _; The four lenses 84 also produce illuminated areas on said array 46, and the array of pixels 46 can be seen, for example, with hardly visible shallow defects. Especially if they are in the inner part of the lens, a bright outline appears in the dark field on the 46-pixel array. If it is in the peripheral zone of the lens, this defect will be visible in the pixel array 46 as a dark line in a bright field. The peripheral zone of the contact lens, due to its wedge-shaped cross-section, refracts the transmitted light to the extent that this light passes the cap 40 and causes the whole of the z-zone Z-haZL to appear as a bright, white ring ! 1 ί on Line in v; ι: field.

It will be appreciated that any suitable light source, lens and camera can be used with subsystems 14 and 16. For example, the light source 30 may be a short arc flash lamp (manufactured by Hamamatsu). This flash lamp has a unique combination of stability and arc lifetime, with a lamp power rating of plus or minus 2% at 10 flashes.

Further, with respect to the embodiment of the subsystem 16 which has been actually reduced for practice, the first imaging lens 54 is an achromatic lens with a focal length of 100 mm, which is diffraction-limiting for objects within 2.5 ° of the optical axis of the lens. The lens 54 is mounted in a dark anodized tube with internal reflective surfaces 60 that eliminate the deterioration in contrast that could occur due to light reflection from the inner walls of the tube. The second lens 56 is a standard Nikon F lens. 1.8 with a focal length of 50 mm. The end of the cylinder of the first lens 54 is adhered to an ultraviolet turbid filter that is screwed into the 50mm lens cap.

The opaque cap 40 is formed by a small plastic ring with a diameter of 2.54 mm having an adhesive back side allowing the cap to be fixed in place. Suitable caps are commercially available caps which are used as solder backing masks for the manual manufacture of flat plate panels and are available in many different sizes. The preferred size of stop 40 may vary depending on other parameters of system 10 and the selected size of the stop is preferably chosen to provide the best compromise between growth-Confederation m -, - Stronger SFE-sn-t-rectifies them n'Í7 ^_ and ^_ 'c it Ti' ve ší '' na ^- VÍ dragon ^- . ......

The camera used in said subsystem 16 is a high-resolution Videk camera having a standard one

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Nikon. Nikon's 56 Fl, 8 / 50mm camera lens is attached to the lens and the lens cover 54 is then screwed onto the lens. The effective field of view of the camera is 13.8 x 13.8, which is about 10- 15% greater than maximum contact lens size. Desirably, the ophthalmic lens to be inspected occupies exactly that portion of the field of view of the camera 36 that would permit optimized inspection. Thus, by automatically centering the inspected lens, the control bowl 110 of the lens carrier 22 maximizes the achievable camera resolution.

Preferred configurations of subsystems 14 and 16 have many advantages. First, since the light path 82 is refracted, the light source 30 may be located at a greater distance from the optical lens that is in the control position 144, thereby substantially collimating the light rays on the lens. Second, the image size of the arc on the cap 40 is substantially equal to the actual size of the arc. multiplied by the ratio of (i) the distance between the light source 30 and the lens 54 / (ii) the distance between the lens 54 and the lens cap 40. The preferred arrangement (see figure · 8) still minimizes the t image size of the arc and consequently provides higher sensitivity. Third, the iris diaphragm 130 limits the cross-sectional area of the light beams 82 and hence the area illuminated by this light γ. Preferably, the aperture 130 is used to adjust the cross-sectional area or size of the light beam 82 so that the beam 82 illuminates a circular surface whose diameter is only about 10-15% larger than the diameter of the inspected ophthalmic lens. By limiting the size of the illumination beam 82, the contrast between the image produced on the pixel array and the remainder increases, in particular, the amount of light scattered by the lens-like control dish is eliminated or substantially reduced. This scattered light may appear as a background light on pixel array 46.

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The contrast between the obstruction between the subject matter of the pixel seukuptnx 46 and the remainder of this grouping 46.

Further, with respect to the preferred configuration of the subsystems 14 and 16, the magnification factor is the image size ratio »

the lens of the pixel array 46 to the actual image size, approximately equal to the ratio of the focal length of the second lens 56 / the focal length of the first lens 54. The actual magnification factor further depends on the distance between lenses 54 and 56 and the distance of the checked lens from In addition, the evasion member 140a and the slider 140b allow the center of the beam input beam 82 reflected from the mirror 34 to coincide with the axis of the imaging optical subsystem 16.

As already described, the imaging subsystem 16 comprises two lenses 54 and 56 which are spaced apart approximately at a distance equal to the focal length of the first lens 54. Although the use of two lenses in the subsystem 16 is not necessary, it is preferred to provide more control of the various parameters of subsystems 14 and 16 and suppress, for example, the distance between the rear, focal plane and the display plane.

Figures 11A, 113, and 11C illustrate alternative optical arrangements, generally designated by reference numerals 152, 15, 4, and 15, respectively. 156, which can be used in the guidance system 10, the beam of light beams 32 by the control position, hold the eye lens with the "v 'te tΌ" * "ρ'ο l" o * zeT "at 40 ~ ^ a- p ix e lo vé — S es ku- —---- foaming'46.

The arrangement 152 includes only one lens 160 that simultaneously displays a beam 82 of light rays on the cap 40 and a controlled lens on a pixel array

46. More particularly, the optical arrangement shown in Figure 11A includes a mirror 162, an imaging lens 160, and an equator cap 164, a controlled eye lens 166, and a pixel array 46. For this arrangement, the beam 82 or pulses faces away from the light source 30 to the mirror 162, which further directs this light through the lens 166 towards the imaging lens 160. Most of the light directed at the lens 160 is focused by the lens onto the cap 40, but certain features of the lens 160 will refract the light to the extent outside the cap 40 and focusing on the pixel array 46, forming an image of the lens feature 166 that caused the light to be refracted and transmitted beyond said cap 40. The arrangement of Figure 11A may be advantageous when the CCD of the camera 36 greater than CCD aperture above Vidik cameras with high resolution.

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Referring to the arrangement 154 shown in Figure 11B, the functions of imaging the light source on the cap 40 and imaging the inspected eye lens on the pixel array 46 are separate. To achieve this, the arrangement 154 comprises a mirror 170, a lens 172 and 17 and a cap. 40, wherein. Figure 11B further shows the lens holder 164, ophthalmic lens 166, and pixel array 46. In this arrangement, the light beam 82 from light source 30 is directed to mirror 170, which mirror directs beam 82 onto lens 172. Through the lens 172, directed light passes through the eye lens 166, most of the light that passes through said lens 166 focuses on the cap 40. Some features of lens 166 refract light outside said cap 40, the refracted light impinging on lens 174 which focuses it on the pixel array 46 on which it forms The advantage of the lens arrangement of FIG. TIB is that the action of the lenses 172 and 1774 is completely independent of one another. _______

The optical arrangement 156 shown in FIG. Fig. 11C is very similar to the optical arrangement shown in Fig. 8, but this arrangement 156 does not include a mirror 32 or an aperture 130. More specifically, the arrangement 156 includes a mirror 176, lenses 180 and 182 and a cap 40, Fig. 11C further showing the lens holder 164, ophthalmic lens 166; pixel grouping 4 6. Referring to this arrangement shown in Figure 11C, the light beam 82 directs from the light source 30 to the mirror 176, which in turn directs this light through the lens 166 to the first lens 180. most of the light directed towards the lens 180 is focused on the cap 40, some of the features of the lens 166 refract the light to the extent that it passes beyond the cap 40 beyond the cap 40 onto the second lens 182, the second lens 182 focusing said light on the pixel array 66. In this arrangement, lens 180 shows a light source 30 on the cap independently of lens 182. However, both lenses 180 and 182 are involved in imaging any defects of lens 16 6 on pixel array 46.

In addition to the already described, the system 10 preferably further comprises a control subsystem for synchronizing the operations of the lighting subsystem 14 and the display subsystem 16 with the operation of the transport subsystem 12, in particular starting the light source 30 to generate light pulse and open the camera lens 50 The preferred control subsystem is shown schematically in figure "r2A". "" Cb "" sweep "" of this "" preferred control subsystem, the transport subsystem 1 2 generates an electrical signal each time the lens-shaped inspection bowl is in the inspection position. This electric

For example, a stepping motor 94 or other excitation means of the translation plate 92 and / or a limit switch that closes each time the control tray reaches the control position can be used. Preferably, this signal is transmitted to the camera lens 50 to open the lens. 50 and a delay circuit 184 that delays this signal within a short period of time, allowing the camera lens 50 to fully open, after which the electrical signal arrives at the illuminator driver which activates the light source 30.

For example, in the embodiment of system 10 shown in Figure 123, when the ophthalmic lens is in the control position, the transport subsystem 12 generates a 24 volt pulse and transmits it to both the camera 36 and the delay circuit 18 4. Lens 50 of the camera 3 6 opens in response to the face of this pulse, and about 9 milliseconds are required to fully open the lens 50. The delay circuit delays the transmission of this signal to the illuminator driver 34 for about 15 milliseconds, after which the trigger pulse is transmitted to the illuminator driver. The face of this triggering pulse activates a tiristor (SCR) that ignites the flashing bulb 30. At this point, the illumination body becomes electrically conductive and the capacitor charged in the previous phase is now discharged through the illumination body. The capacitances and voltages at which the capacitor was charged determine the total light energy emitted by the illuminator and the duration of the light pulse. Meanwhile, the internal periphery of the camera 36 leaves the lens 50 of the camera 36 open for about 30 milliseconds and closes it after this time period.

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The use of the camera lens 50 in the manner described above prevents or at least substantially reduces the possibility of integrating ambient light in the pixel array 46 between individual controls. The high voltage power source, the illuminator driver, the electrical and storage capacitor are preferably housed in a housing 26 in which the lighting optics is also stored.

The light from the light source 30 is sufficient to allow the image to be captured on the pixel array 46 in such a short period of time that it is not necessary to stop the movement of the ophthalmic lens to be inspected. Thus, the transport subsystem 12 is preferably designed to move a plurality of ophthalmic lenses beneath the display subsystem 16 continuously. This continuous and continuous movement of the array of ophthalmic lenses is further advantageous in that it reduces or eliminates the formation of ripples or other rupture of the upper layers of solution 112 contained in the control dishes 110, which may interfere with the imaging process.

It will be apparent to those skilled in the art from the above description that various procedures may be used to achieve the desired synchronization and coordination between the transport subsystem 12, the lighting subsystem 14, and the display subsystem 16. For example, the light source 30 may be activated at predetermined time intervals that correspond to the positioning of the control ophthalmic lens in the control position 144 as well as the opening of the lens 50 of the camera 36.

In order to minimize the effect of airborne debris and lighting and imaging processes, the lighting, imaging and transport subsystem can be housed in a housing (not shown). The housing may be transparent. a front door or a front door having transparent windows, allowing both entry into and observation of the inner part of the housing, and the latter can be read for reasons of minimization the effect of ambient room light on the lighting and imaging processes is toned.

*

In this subsystem, electrical signals from a group of 46 pixels are routed, in combination of series and parallel formats, to a preprocessor 62. These electrical signals that are transmitted to the preprocessor 62 The processor 62 may be identified by any suitable method using the specific pixels that generated the signals. The signals from the pixels of the camera 36 may be transmitted, for example, to the upstream processor in a given time sequence and together with a time signal which makes it possible to identify the origin or selected intervals of that time sequence. Alternatively, the individual signals that are transmitted to the processor 62 may be provided with a header or other note that identifies the respective pixel that generated the respective signal.

The processor 62 converts the individual electrical signals from the individual pixels of the array 46 to the corresponding digital data values, 1, and stores these data values in a memory area containing addresses associated with the pixel addresses that generated the electrical signals. These data values are available for the processor 64, to which they can be transferred via data buses 186. As will be explained in more detail below, preferably a plurality of additional data-value sets 1, ... 1 are generated, each data set having a particular data1 n ¹ , a value associated with the individual pixels of the array 46, wherein the advance processor 62 may include memory sections or plates, and each of these sections or plates is used to store a respective set of said data values.

The processor 64 is connected via the data bus 186 to the advanced processor 62 to obtain and transfer data values from the processor 62 to the processor 64. As will be explained in greater detail below, the processor 64 is programmed to process and analyze the data values stored in the processor. 62a to identify at least one condition or parameter of the individual lenses controlled by the system 10, for example to determine if the individual lenses are acceptable for use by the consumer.

A memory disk 70 is attached to the processor 64 to receive the data on a permanent or semi-permanent basis to the processor 64. The memory disk 70 may be equipped with various lookup tables used by the processor 64. The memory the disc may be used to store lens inspection data or data collected during the inspection. For example, the memory disk may be used to closely monitor the total number of lenses checked during a given day or other time period and to store information about the total number, type and size of any defects detected in any given sample or group of lenses.

A keyboard 66 is attached to the processor 64 to allow an operator to enter said processor 64, wherein the keyboard terminal 74 is used to display data or messages that are input to the processor 64. The monitor 62 is connected to a monitor-monitor. 72, which converts the data values stored in the upstream processor 62 into their image form. For example, the data values I may be transmitted to a monitor 72, the purpose of which is to produce on the monitor 72 an image corresponding to the actual image formed by an array of 46 pixels. Other data-value files may also be transferred to the monitor 72 to produce accurate or processed images of the actual image. Further, a printer 76 is connected to the processor 64 by means of a serial-parallel converter 190 to provide a visual continuous record of selected data values transferred from the processor 64 to the printer 76. It will be appreciated that the subsystem may be equipped with additional or auxiliary input and output devices enabling the operator; or. analyst interacting with processor 64, upstream processor 62, and storage unit 70.

The various components of subsystem 20 are known and commonly available. The processor 64 is preferably represented in the subsystem 20 by a high-speed digital computer and as a monitor 72 is

ΓΊ.ΓΊ 1 “r i

for example, the upstream processor 62 may be a signal processing card assembly of Datacube, and the processor 64 may be a Sun 3/140 workstation.

As mentioned above, at some point in time, an ophthalmic lens passes directly below said camera 36, and through the ophthalmic lens passes light that focuses on a group of 46 pixels, the individual pixels of group 46 generating corresponding output electric currents of magnitude represents the intensity of light incident on these pixels. This individual pixel output stream is converted to a digital data value that is stored in an address in a memory associated with said pixel of the upstream processor 62. These digital data values, designated as I values, are, as will be described in greater detail below, processed to determining whether the lens passing under the camera 36 includes one or more features of a selected group, and in particular to determine whether said lens does not contain a feature that could be considered as a defect or defect that makes the lens unacceptable for use. Λ consumer.

Figure 14 illustrates the main components of a preferred image processing process for identifying any defects in a lens 84 of the type shown in Figures 2 and 3. After a lens image is obtained on a 46 pixel array, this image is tested by a procedure referred to as a decentralization test to determine the inner and outer peripheral edges of the ring 84c of the lens 84 are centered with each other, the decentralization test using a fitting of the first and second rings to the inner and outer edges of the ring formed on the pixel array. This is followed by detecting or withdrawing the actual edges of said ring. Then, in order to reduce or completely eliminate data associated with light reflected or deflected edge regions of the lens inspection dish, the first masking procedure is used, wherein edge defects are enhanced by the pOS -up.

O. k, u oj L. X. i-lil ‘* O p C J 4. o 'Chfck belt. These defects can be further accentuated by procedures known as fill and clean and a second masking procedure that eliminates data associated with certain pixels near the center of the ring image.

After the possible defects are highlighted, they are examined to determine if these defects actually exist. In particular, the pixels of the array 46, and more specifically the data values associated with those pixels, are surveyed to identify the lines or processed portions of the pixels that may be part of the defect, and the processed portions are then grouped to identify the defect candidates. Subsequently, the sizes and positions of these proposed defects are analyzed to determine whether the defects they actually make are listed. lenses not fit for consumer use.

As already mentioned, the decentralization test determines whether the inner and outer peripheral edges of the ring 84c of the lens 84 passing under said camera 36 are concentric. Generally, with respect to Figure 15, this test is performed by creating a plurality of scans 202 on pixel array 46, more specifically by studying data values in addresses in the memory of the upstream processor that correspond to the pixel addresses in the selected line on array 46.

The decentation test or program R ^ is shown in the figures. 16a and 16b. The first step 204 is referred to as a threshold subroutine, the purpose of which is to assign to each pixel a new intensity value, equal to either the maximum or minimum illumination, T max depending on whether the original value or T. , min

The-1-e-n-1-i-indicated pixel on or below. given limit o

a value _t T · Thus, for instance, each pixel having an original illumination value Io greater than 127 may be provided with a new illumination value I, equal to 255, and each pixel having

127 or lower may be a new illumination value I equal to zero

The next step 206 of the decentralization test is to collect the number, position, and size of the scans 202 used in the test, by providing the processor 64 with the default pixel address and the length and direction of each scan. These parameters are selected such that, unless said lens is poorly decentrated, all scans from said plurality intersect the two edges of the ring 150. Preferably, the processor 64 or the memory disk 70 is provided with semi-permanent recording of these default addresses, directions and scan lengths. This record is used during the inspection of all lenses of a given nominal type or size, and if the lenses of a different nominal type or size are checked, this semi-permanent record may be replaced.

In the next step 210, selected scans are created on the pixel array or display 46 '. Unless the lens is decentralized, most of these scans cross the illuminated portion of the display. When the scan intersects the illuminated portion of said display, the addresses of the first and last pixels of said line intersecting the illuminated portion, and the lengths of this line, designated as the section being processed, are recorded in file f. . Subprograms for detecting the first and last pixels of a given processing section, for obtaining the addresses of these pixels, and for determining the length of each processing section are known in the art, and any suitable subroutine can be used in the decentralization test.

In the next step 212, the length of each processing section is compared to a predetermined value, and information, which is the addresses of the first and last pixels in the processing section, and its length associated with each processing section less than said predetermined value, including. The method is to imitate, or at least reduce, the amount of data caused by noise on the pixel array 46, meaning unwanted light that impinges on the pixel array. Noise, which may be due to ambient light or light that deviates from the desired light path due to dust or other particles, may create illuminated areas on the pixel array. In the vast majority of cases, all of these illuminated areas consist of only one pixel or a small group of adjacent pixels. If any of the above scans created in step 210 intersect this illuminated area, the processor records the addresses of the first and last pixels and the length of the processed section crossing the illuminated area. These illuminated, however, do not relate to the ring area and its associated data with 162 or its edges, and the target step

212 is thus eliminating this data.

The next step 214 of the decentralization test is to identify the addresses of all remaining pixels that are on the outer or inner edge of said ring, and any suitable program can be used to identify this. . For example, the addresses of the first and last pixels of all processed sections may be compared to each other, and a -pixel that is closer to the center of the entire array of 46 pixels may be considered to be a pixel lying on the inner edge of ring 162 from the center of the array 46, it can be considered to reside at the outer edge of the ring. Or scans may be separated into two groups such .že all the 'Scan-in ^půfvňí' s'kuprně "pl-ATI-7 if it is found during the scan illuminated run length, the first and last pixels in the run length are on the internal resp. the outer edge of the ring, and for each

In the second group, if the illuminated processing section is found in the scan, the first and last pixels of the processing section lie on the inner and outer sections, respectively. an outer edge of said ring.

After all the pixels lying on the inner and outer edges of the ring have been determined, a step 216 follows, in which all the pixels that were discovered at each edge are added up. If the sum of the pixels on one or the other edge is less than three, then in the next step 220 the lens is discarded due to its poor decentralization. However, if at least three pixels are detected at each edge, then in step 222, a subprogram is used in which, first, the first circle is fitted to the pixels that were discovered on the outer edge of the ring, and the second circle is fitted to the pixels that were detected. on the inner edge of the ring and thirdly, the centers and diameters of the two rings are determined. A number of programs are known to fit a circle to three or more points and to calculate the center and diameter of the circle that can be used in step 222 of the decentralization test.

After the centers of the two mating rings are calculated, the distance between the two centers is determined in step 224. This distance is then compared in step 226 to a first value _d1, and when the distance * 'greater than d _1, the lens is in the following step 230 rejected as being badly decentered. If the distance d is less than dp &apos;, in step .232, the comparison of the distance d with the value d &apos;, which is the maximum acceptable distance between the centers of the inner and outer edges of the ring 150. at step 234, it is discarded as decentralized, but if the distance d is equal to or less than d 4, then the lens has passed the decentralization test, as indicated at step 236.

When the lens has undergone a decentration test, the processor 64 initiates a procedure, or program called an edge detector, to create a set of illumination values that, in turn, can be used to identify pixels at the edges of the lens. 150. These edges are not usually accurate circles, and thus differ from the mating circles introduced during the decentralization test. This new set of illumination values is obtained by a series of morphological operations or changes in the original intensity values assigned to the individual pixels of group 46. These morphological changes are illustrated pictorially in Figures 17a to 17i and in the form of a flowchart in Figure 18. More specifically, Figure 17a depicts a ring image 150 to a group of 46 pixels, and Figure 17b shows an enlarged view of a portion of the ring, and also shows short lines 240, or scans, intersecting the annular portion and adjacent areas of the pixel array 46. Figure 17c illustrates intensity values of said pixels in this scan 240, pixels in the dark areas of Figure 17b have a lower or zero value of 1 ^, and pixels in the light areas of Figure 17b have a higher value of 1 ^, for example T

..... -max ......- .....-..... -. . ........ ..

Referring to Figure 18 and Figures 17c and 17d, in the first step 242 of the edge detector process, a new value of 1 is calculated for each pixel, in particular the value for each pixel being equal to the mean value of that pixel and its eight immediately adjacent pixels. The difference between the I and I values for these pixels in group 46 is that the values change by jumping from the pixels having the lowest I ₂ value (pixels that lie in the dark areas of the pixel grouping) to the pixels having the I ₂ value highest (pixels, which lie in the light areas of group 46). This difference can be best understood when comparing Figures 17c and 17d.

Next, at step 244 assigns the value of each pixel through another, not it is assigned to each pixel HQD-n.Qfca ij _f _k.terá_j.e_s.hodna_s_m.inimální I ₂ value of that pixel and its eight immediately adjacent pixel neighbors. Referring to Figures 17d and 17e, the way in which values change over a pixel scan is similar to the way in which values 1 change between the two highest values of the highest value of I ₂

In uiXel's scan methods, the band of pixels having is slightly narrower than the band of pixels having

Next step

246 of the procedure referred to as the edge detector should determine for each pixel another value X ₄ according to the formula = I ₂ - I. With particular reference to Figure 17f, most pixels in scan 240 have a value of zero, but pixels adjacent radially immediately to the inside of both edges of ring 162 have positive values of I. In the next step, the value of I &apos; is determined for the individual pixels, wherein the value of I of each pixel is more precisely equal to the maximum value of the I1 pixel and the eight immediately adjacent pixels. For most pixels in pixel grouping 46, the value matches those of those pixels. However, for pixels lying within the range specified by ·. the distance of said edges of the ring 150, the Ig values of these pixels are greater than the I values of said pixel, and the band of pixels having a higher I-value is slightly wider than the band of pixels having a higher I-value.

The next step 252 of this procedure is to determine an additional Ig value for the individual pixels, which value is selected from the relation I, = I _c - I-. Referring to Figure 17h, most pixels on the pixel array will have an Ig value of zero, but the pixels adjacent radially immediately to the outside of both edges of the ring 150 have positive Ig values. The next step 254 is to assign the value Ij to the individual pixels, more precisely the value I _? individual pixels is equal to or less than 1 µg and Ig. Referring to Figure 17i, most pixels of pixel array 46 are I _? but the pixels lying directly on the edges of the ring 150 and the pixels immediately adjacent to them have positive values of I. determine which pixels are on the edges of the ring.

Subsequently, in step 256, a delimiting subroutine may be used to highlight the difference between the pixels at the edges of the ring 150 and the other pixels on said display. Each pixel may be assigned a still further value _a which is equal to either the minimum illumination intensity value T 0. or the maximum value of illumination intensity min

T depending on if the value of the said I, the pixels max ^J 7 ^{r are} lower or higher than the given threshold value T. So, for example, every pixel having an I? greater than 32 may have a Ιθ value of 255 and each pixel having an I value? a value of 32 or less may be assigned a value Ιθ equal to zero.

Figure 17j shows the illumination of the individual pixels of the cluster .46, at an illumination value of these pixels equal to θθ.

During the calculation and processing of the values up to θ, preferably each set of pixel values is stored in a separate memory register in the forward processor 62, so that. for example, all Ιθ values are stored in the first register, all 1 ^ values are stored in the second register, and all Ιθ values are stored in the third register. It is not necessary to keep all values 1 ^ to Ιθ throughout the processing process, but some values may be discarded in individual processing periods. For example, once I values have been calculated, Ιθ values can be discarded as well as lzeθ values can be discarded after I stanovení values have been determined.

In addition, it is not necessary to calculate hodnθ values. to Ιθ for all pixels of said array 46. For any ophthalmic lens of a given type, the lens ring will appear in a relatively-defined-area-or region-of-the-art pixel area. In group 4.6, only s nutné stanovitθ values need to be determined for the pixels that lie in this area. However, from a purely practical point of view, it may be easier to calculate these values. X * 1-,, -4 --- J.

k.? Accordingly, the former would require the introduction of an additional processing step to identify those pixels that are in the region of interest.

Upon completion of the edge determining program, a masking program is run to form a set of pixel illumination values I that does not contain pixels whose illumination is due to the features of the edge of the control bowl that is used to hold said lens. The ophthalmic lens is illuminated by a flash of the illumination body 30, and the transmission of light also occurs through the inspection cup holding the lens. The dish edge may deflect a portion of this light to the extent that it passes outside said cap 40 and hits the pixel array 46 where it forms an image or partial image 260 of the dish edge (see Figure 19a). The image of this edge does not relate to the inspected lens itself, and all data associated with the image of the dish edge is unnecessary and undesirable for evaluating data related to the image of the lens itself. A masking program is used to eliminate the bowl edge image from the pixel array 46, and more specifically, to create a set of pixel illumination values that is free of pixel data associated with the above bowl edge image 260.

Figure 20 shows a flow chart of a preferred masking program R. The first step 262 of this program has. to determine whether at least three pixels were detected at the outer edge of the ring 162 at step 216 or 226 of the decentralization test or whether in one of these steps said ophthalmic lens was found to be poorly decentrated. if the lens is found to be poorly decentrated, the masking program R 'ends automatically at step 262.

If program R ^ is not terminated in step 262, it proceeds to step 264 to determine the coordinates of the center of the circle, which is-1-sl-e-n-with-outer-edge-150, and-ring-T5Q-. during the decentralization test. These files were stored in the memory of the processor 64 or in the disk memory 70 during the decentralization test and can therefore be easily retrieved simply by recalling from memory. After these center coordinates are obtained, the mask subroutine is used in step 266. With reference to the accompanying picture

19b, this subroutine actually overlaps the pixel array 46 with a disc mask 270 having a center having the aforementioned center coordinates and a diameter slightly greater than the diameter of the circle aligned with the outer edge of the ring 150.

The masking subroutine then assigns a value to each pixel

Depending on whether said pixel lies inside or outside of said mask 270. Thus, more precisely, to each pixel outside said mask 270, the masking subroutine assigns a value equal to zero and to each pixel lying within the mask. - 270., .. allocates ... listed. _ masking _ subroutine. value Ιθ equal to the Ig value of the pixels in question.

More precisely, in step 266, the coordinates (χθ, Y _Q ) of the aforementioned center point and the radius value r ^, which is selected to be slightly larger than the radius value of the circle aligned with the outer edge of the ring 150, are transferred to the masking subroutine. creates an address file of all the pixels of the grouping 46 that lies within a range that is given by the distance from the center point

- (x Λ Y _Q ). Then, in step 272, it is checked whether the addresses of the individual pixels of the group 46 are contained in the .tomt.o file.

If there is already a pixel address in said file, then in step 274 said pixel is assigned an Ig value equal to I _by that pixel. However, if the pixel address is not in

Then, in step 276, a zero Ig value is assigned to said pixels.

Any suitable step can be used in step 266 of R &lt; 1 &gt;. a masking subroutine, since a number of suitable subroutines are already known today.

Figure 19c shows an illuminated array of 46 pixels, with an individual pixel intensity equal to Ig,

Upon completion of the masking process shown in Figure 20, the processor 64 initiates another process, referred to as the elastic band algorithm. The algorithm generally employs the analysis and processing of pixel data values or data values associated with the pixels at the edge of the ring 150a and in its immediate vicinity, with Figures 21a and 21b showing a flow chart that generally outlines the elastic band algorithm. Referring to these figures, in a first step 280 of this algorithm, the center coordinates and the diameter of the circle aligned with the outer edge 150a of said lens are determined in a decentration test. As already mentioned, these values have been detected and stored during the decentralization test and can now be retrieved in said memory.

The purpose of the next step 282 of the elastic band algorithm is to locate a pixel at the outer edge 15a of the ring 150, wherein the survey is performed from the left edge of the pixel array 46 inward. This survey will be terminated only after the illuminated pixels have been found. It is possible that the first illuminated pixel detected during said survey will not actually lie on the edge of the image of said lens, but somewhere in front of it (meaning downstream of the survey), the illumination of such pixels being the result of background noise. Therefore, preferably at step 282, multiple scans or surveys are performed to discover a plurality of illuminated pixels. The positions of these pixels are further analyzed and compared to each other to more accurately determine the position of the individual pixels, more accurately determining that the discovered pixel actually lies at the edge of the lens image.

Upon detecting the first time the lens has been first opened, the elastic band algorithm proceeds to step 24, and at this step the algorithm begins to substantially encircle the edge of the lens image, starting at the first illuminated pixel and eventually into the first illuminated pixel. pixels returned.

During the first circling, the algorithm records in the file f the addresses of most or all of the pixels at the outer edge of the lens image, identifying the larger gaps at that edge, the length of these gaps, and the larger unusual portions at that edge. In the next step 286, the algorithm records in the file the addresses of those pixels that are the endpoints of the selected lines, described in more detail in the following section, which are plotted to intersect all larger gaps in the lens edge and connect one side to the other parts with this edge.

the end of the first-circling - around .... the picture. In step 290, the elastic band algorithm determines whether any of the gaps detected are large enough to have to be discarded. If such a gap is detected, the lens is discarded and in step 292 the printer prints a report indicating that the lens has a bad edge.

If the lens passes this test, the elastic band algorithm proceeds to the next step 29Q, in which it encircles the edge of the lens image a second time. In this second circumference, in step 294 (FIG. 21b), the algorithm identifies surface features such as smaller gaps and smaller unusual portions extending. The algorithm tests all of these detected features to determine if the detected features should be discarded. This is usually done by calculation, and for all selected pixels, a scale of three products of two vectors, designated as a radial vector and an edge vector passing through the respective pixel, is calculated. A radial vector passing through a pixel is that vector that also passes through the central rings .152. which has a more passing edge against the direction of the point of the circle flush with the outside. edge 150a The edge vector passing through the pixel is a vector with a given pixel and a given number of pixels on the ring 150 lying behind said pixel, clockwise.

For any pixel on a regular circular portion of the lens edge that includes no defect, no gap, or a domed portion, the scalar product of the two vectors specified above will be substantially zero, since the radial vector and the edge vector are substantially perpendicular to each other. However, for most pixels, or for all pixels at the edge of the gap or the domed portion of the lens edge, the scalar product of the edge vector and the radial vector passing through said pixel will be non-zero since the two vectors are not perpendicular to each other. If any calculated scalar product is greater than a given value, then the lens is considered unsuitable for consumer use and may be discarded.

If the lens passes tests applied during the second revolving around the edge of the lens, then the elastic band algorithm ⁴¹ performs a third revolving of the edge of the lens image shown in step 296 in Figure 21B. This third encirclement does not include any test that should determine whether or not the lens should be discarded, but instead introduces data processing and preparation for subsequent tests. More specifically, this third ring is provided to provide a set of data values that will not contain data associated with any lens defects located within the outer edge 150a of the ring 150. This set of data values is then subtracted from the data set. values containing data associated with said defects, thereby providing a set of data-values having only data associated with said defects.

Usually, in the third circumference of the lens edge, the elastic band algorithm determines the mean radial outer thickness. The edges 15 and 15 are then and all of the pixels that are just inside the outer uranium rings are shown.

For example, if the outer edge of the ring has a mean thickness of six pixels, then the elastic band algorithm can assign a zero Ig value to all pixels lying between 7 and 27 pixels, calculated radially inward from the outer edge of said ring.

Figures 22 to 32 show the elastic band algorithm in more detail. More specifically, Figure 22 illustrates a suitable subroutine for determining the position of the first pixels

P (x, y) on the outer edge '150a of the annulus 150. At step 300, the (x, Υθ) is assigned the coordinates of the center of the circle that was fitted to the outside edge of the annulus during the decentration test at step 302 and r is the radius of the outer _Q assigned merged circle. Then, as shown in step 304, a plurality of horizontal scans intersecting the pixel array 66 are formed, beginning at the center or near the center of the left edge of said array. More specifically, the processor 64 studies data values of Ig in addresses stored in the memory of the upstream processor that correspond to the pixel addresses in the selected horizontal lines per pixel array. When each scan is scanned, the processor 64 checks the value of each pixel in a given horizontal plane of the pixels and identifies the first pixel in that plane whose Ig value is greater than the given value, preferably a plurality of such groups being formed that get a set of identified pixels.

——- ob you ki-e- ~ b u u u-all ny “ty t cr ~ i * dentrfi k‘o in ahfé“ p-i x’eTy “Le-”

Although the pixel lying anywhere to the left of said edge on array 46 may have a high Ig value, which may be due to background noise or deflection of light incident on the pixel during the lens inspection procedure, and this pixel can be identified as an illuminated pixel in the aforementioned scan. In order not to identify these pixels as edge pixels, a subroutine S is introduced, which in step 306 identifies and defers the addresses of all these pixels. More precisely, the subroutine first determines the distance between the individual pixels identified in the scans and the center (x, y _Q ) of the outer circle aligned with the outer edge of the lens image during the decentration test and secondly compares the individual determined distances sr. . If the distance between an individual pixel and the center of said matched circle is greater than ro by more than a given distance d, then that pixel is considered to be at or immediately adjacent to said edge 150a of ring 150 and the address of that pixel is postponed. After the addresses of all the pixels detected during the scan have been checked and found to lie on or adjacent to the lens edge, at step 310, any remaining pixel address can be selected as the starting pixel address P (x, y} and subsequently, the first edge of the image of the lens can be initiated.

Image. 23 shows in greater detail the manner in which the first encirclement is made, and in particular the program for performing the encirclement. The large-gap examination at the edge of the ring or at the domed portion at that edge, represented by steps 3,14 and 320, performed by the algorithm begins at step 312 in pixel P (x, y) and continues clockwise along the outer edge of said ring 150 Any suitable subroutine or procedure may be used to conduct a survey along that edge. When started at pixel P (x, y), the processor can examine the three or five nearest pixels in a row above or below that pixel or column to the right or left of that pixel, depending on the quadrant or sector of display 46 in which the pixel is located to identify another pixel at said lens edge. The processor may use the same procedure to identify the next subsequent pixel on the lens edge.

Furthermore, the pixels that have been detected at the edge of the lens can determine the distance r by the pixel and the center point (x, x, y, x, y, y).

V) a circle flush with the outer edge of said lens. The processor may decide that a large gap has been found if, for each pixel of a given number of consecutive pixels at the edge of the lens, r is less than ro more than a given amount of d (r, -r> d). ^J ogog

On the other hand, the processor may think that a large domed portion has been discovered if all the pixels in a given set of consecutive pixels at the lens edge have r greater than r _Q by more than a given amount (rr _Q > d _eo

If there is a gap or an arch, in steps 316 and 316, respectively. 322 used subroutines respectively. Which will be described in more detail below. However, if neither a gap nor a domed part is discovered, then the proportions of qram · -R- ^{T go} to step 324n ---------—.....-- -------- At step 324, the -R program examines and determines whether the first ring edge 150 is completed, and can be used for this step. any appropriate procedure or subroutine. For example, as discussed above, when a lens image is encircled along the lens edge, a file containing pixel addresses that have been discovered at the edge is drawn, at step 324, the file may be examined to determine whether the address of the last pixel If the address of this pixel is already present, it will be recorded from the edge (ascertained in the direction of encircling). The edge along the edge of the lens image is considered to be terminated, but if the address of the last pixel is not yet listed, the image of said lens is not terminated. If the first pass is complete ,, then the algorithm proceeds flexible Fr ^- ^ in the program but if the 'first pass around the lens is not complete · the algorithm moves to step 326 and the address of this current edge pixel being considered is added to file f Then, in step 330 P (x, y.) Ί ε compares for the discovery of the next pixel at the lens edge with the address of that next pixel, and the program then proceeds to step 312.

Figure 24 outlines a subroutine 60 that is used whenever a gap is found at the outer edge of the ring 150. The first step 322 of this subroutine is to identify and record pixel addresses at the beginning and end of the gap and the distance between the two ends of the pixels. These two pixels are designated as P ₁ and P _{1 in} FIG. After the gap is discovered, that is, if a given number of consecutive pixels r is less than r _Q by more than d, the last pixel on the edge of the lens before the given number of consecutive pixels can be considered as a pixel at the beginning of the gap. '

Upon discovery of the gap, it may be due to the survey conducted through the gap along the pixels lying on the circle that was flush with the outer edge of the lens during the decentration test and through the radial inward and outward survey for a given number of pixels from said portion the end of the gap is detected when the edge of the lens, i.e. the illuminated pixels, more precisely the pixels having a high value of 1, is discovered. After the lens edge has been discovered, i.e. after a series of consecutive pixels have been discovered, all of which lie some distance from the fused circle, more precisely, for all the pixels of that series that r _Q -r is less than d, the gap can be to be considered completed. The last pixel on the edge of the lens before said series of consecutive pixels can be considered as the pixel at the end of said gap.

is the pixels on the line indicated in the illustration

I _Q , which is equal to the intensity y, returns the subroutine k

At step 340 of the subroutine, a maximum illumination value is assigned as a line between pixels p1 and P1, 25b, and then program R1. Figure 26 shows a flowchart of subroutine S1 used in step 322 of the subroutine. In the event that a domed portion 350 is detected at the edge of the ring 50. In fact, the first few steps of the program are intended to draw different bridges connecting the lens edge and the domed portion. Specifically, in step 352, the subroutine identifies the pixels P1 and P1 shown in Figure 25b at the edge of the ring 50 at the beginning and end of the domed portion 350, and then, at step 354, the individual pixels on the line joining the line. P ^ and P ^ (see Figure 25c} assigned an Ig value equal to T. Next, in step 356, the subroutine identifies the pixel address Ρθ that lies on the edge of the ring 150 a given number of pixels behind or counterclockwise, beginning of said domed portion 350; at step 360, the pixel ležícíθ on the shaft identifies the "domed portion" that is at a given distance d from the pixels Dáleθ. Further, at step 362a, with respect to Figure 25d, the individual pixels on ^J 3 of section L are between pixels Ρθ and Ρθ assigned value.Ig equals max

Next, at step 364, the subroutine identifies the address of the additional pixels ρ that lie on the edge of the ring 15O ^; a given number of pixels before, or clockwise, the end of the domed part, then in step 3-66 the subroutine identifies the pixel P _o at the edge of the domed part

O at given distance d _c from pixels Ρ In step 370, all □ o 'pixels are ^: ·' on 'line - Ω · “- (see ·. ·· -image — 25e j. · · Between - - pixels - Py and P assigned the value 'I _Q equals T. After the corresponding bridges are drawn, the subroutine returns to R ₄ ·

After the first encirclement of the lens image has been completed along its outer edge, a support program R is used. This program, as shown in Figure 27, is intended to determine whether any gap that may have been discovered during the first edge of the lens edge is wide enough to render the lens unsuitable for consumer use. The first step 376 in the program is to determine if any gaps were actually detected during the first circling of the lens image. If no gap is detected, the program terminates itself and the elastic band algorithm advances to Rg. However, if any gap was detected during the first edge of the lens edge, the program proceeds to step 380. in this step, the widths of the individual gaps are gradually compared to a given value dg and if any gap width is greater than said value d 6, then said lens may be considered unsuitable for consumer use and said lens is discarded at step 382. If no gap width is greater than d ^, the program is R1. terminated and the flexor belt algorithm passes to the Rg program, in which the image of the edge of said lens is circled a second time.

The program Rg shown in Figure 28, as noted above, detects in particular shallow gaps at the lens edge and small domed portions at the lens edge that were not identified in the program R in which the first edge of the lens edge image was glazed as gaps and domes. Specifically, at step 384, the pixels P (x, y) are assigned an address identical to the address of the first pixels of the file f1. Then, at steps 386, 390, and 392, the two vectors are determined and labeled as edge and edge vectors, respectively. a radial vector, and the scalar product of the two vectors is calculated. More precisely, the first vector is a vector passing through the pixel P (x, y), the second pixel at the lens edge and a given number of pixels behind or counterclockwise pixel P (x, y) along the edge of said lens, and the second vector is a radial vector of the ring 150 that passes through the pixel P (x, y). The slope of the two vectors and their scalar product can be easily determined from the pixel addresses through which the vectors pass.

S ořihlédn;

_m image of the oripation of the practice ^

P (x, y) lies on a regular circular portion of the lens edge, the vector passing through this pixel is substantially tangent to the lens edge, as shown in step 394 in Figure 29. This vector V is also substantially perpendicular to the radial vector passing through this pixel and scalar the product of these two vectors and is essentially zero. However, in the case where pixel P (x, y) lies on an irregular portion of the lens edge, for example at the edge of the gap or the domed portion of the lens, designated as 396 and 396 in FIG. 340, the edge vector and the radial vector passing through the pixel P (x, y) are not usually perpendicular, and the scalar product of the two vectors is therefore usually not zero.

The scalar product of these two vectors

In ₂ , steps 4 40 are compared to d given value-d ^. A scalar product equal to or greater than d ^ indicates that there is a noticeable gap or domed portion in the pixel region P (x, y), and such a lens can then be considered unacceptable for consumer use and is discarded at step 404 and the entire program Rg is terminated. If the calculated scalar product is less than d?, This indicates that there was no deviation from the exact circle at the edge of the lens within acceptable limits, and the program Rg moves to step 406. In this step, the program should determine whether the second encirclement around the image of the lens edge has been completed. More precisely, it is carried out from the junction to whether it is a pixel. ..v} ... the last pixel of f ^. If so, then the second circumference is completed and the elastic band algorithm moves to the program R1. However, if step 406 determines that the second encirclement around the lens edge image is not yet complete, then it is in step

408 pixel P (x, y) assigned an address identical to the daTsi pixel address stored in the file f ^, then the program returns to step 386. Steps 386 to 408 are repeated until said lens is either discarded or individual pixels are present In this case, the scalar products from the respective vectors and V ₂ are calculated and found to be less than d 2, at which point the elastic band algorithm passes to the program R 2, which performs a third circle around the edge of the lens.

Preferably, the aforementioned scalar product is not calculated for all pixels at the lens edge, more specifically, this product is not calculated for pixels that are at the edges of the gaps or domed portions detected during the first rounding of the lens edge. It is not necessary that this scalar product be calculated for the pixels of these gaps and domed portions, since it is already known that these pixels lie either on the gap or on the domed portions. By not determining the Vp V2 vectors and the scalar products of the two vectors of said pixels, a significant amount of processing time is saved.

After the Rg program is completed, the elastic band algorithm moves to the program that performs a third orbit around the lens edge. As already mentioned, the purpose of this third encirclement is in fact to create a new set of data values Ι Ι θ which does not contain any data associated with any defect or caries of said lens that edge of said lens. The R? Program, which is shown in greater detail, is generally. In the first part . the pixels assigned hodshodná value I, _Q for a given pixel in the second part to calculate an average edge thickness value, N · for the outside edge 164 of annulus 162; and in the third part of the pixels which lie within the range of the average edge thickness are assigned a zero value Ι ^ θ .

The right on the outside is in 'Figure 30' consisting of three parts of the note which ie

In more detail, at step 410 of the program R ^, all pixels are assigned a value ΙΙ θ that is equal to the value of the individual pixels. Further, with reference to Figures 30 and 31, in step 412 at the outer edge 15a of the ring 150, a given number of pixels, shown in Figure 31 as 414a-e, is selected. • Then, in step 4 '5, the program R _Ί ~ _adds ^- the number of axes spelled out by 1 x 2 2 p. J. C řtit * V. COCky f OZ nSCvJfiy Cil Ilcl UUídZAU Λ ^: such as 420a-e that pass through said pixels 414a-e. For example, the program may count the pixel at the edge of the outer edge of the ring as the first pixel when counting and then add to it all illuminated pixels that appear at said radius in a radially inward exploration of the aforementioned first pixels. In step 422, the average number of illuminated pixels per radius is calculated, which can be done, for example, by simply seeing the total number of illuminated pixels counted by the number of radial scans performed. Usually, this average value is not an integer, and therefore preferably this average value is rounded up to the nearest integer.

In the next part of the program R _? the third encircling of the outer gate is made Ϊ5Oa '~ simply ~ Τ5Ό' In order to be able to start this ^{- the} encircling, at step 424 / at this edge, any pixel is selected as the initial pixel P (x, y) . The selected pixels are then selected in steps 426 and 430. lying behind the average edge thickness in the radial direction and in the inward direction, zero value Ι ^ θ has been assigned. Taking into account the accompanying Figure 32, these steps actually assign a zero value of Iθ to the pixels that are located in the hatched surface 432. In step 434 of the program R1, a check is made to determine whether the third circle of the image of the lens is completed. k - · pro leads to this - how to use any of the appropriate subroutines. For example, if the pixel that was selected as the initial pixel for the third lens edge encirclement, the initial pixel of the file can be considered to be completed if step 426 and step 430 are also performed on the bottom pixel of the file f1. Alternatively, a separate write of the pixel addresses used in steps 426 and 430 of R ' may be used, and each time the list has been updated with a new pixel address, a check should be made to see if the newly written pixel is already on the list. Once the address of this newly inserted pixel is already on the list, the third circle around the edge of the lens can be considered to be finished.

If it is determined in step 434 that the third *.

the circle around the edge of the lens is not complete yet, pixels p (x, y} are assigned an address identical to the address of the other pixels, clockwise, at the outer edge 150a of the ring 150. For example, this address may be removed from file f, and 436 can be pixels P (x,

y) simply assigned an address identical to the address stored in this file that belongs to the subsequent pixels. Then, program R returns to step 426, and steps 426, 430, and 434 are repeated for the address of the new pixels P (x, y).

After this third orbit around the lens edge image, the processor 64 exits the R-program. and said elastic band algorithm is terminated.

Upon completion of the elastic band algorithm, a number of other operations are performed to generally highlight any irregularities in the lens being inspected, thereby facilitating the identification of such irregularities.

The first of these, referred to as fill, is to assemble another set of data-values 1 for the pixels of grouping 46. This procedure can be used to identify pixels in individual irregularities at, at or adjacent to the outer edge of ring 150. More specifically, referring to the figure 33, these data values are used to identify pixels in (i) individual gaps 436 in the lens edge, (ii) in individual irregularities 440 within the lens edge, in (iii) individual domed portions 442 at the lens edge · and (iv) pixels between any extra pieces and the horizontal being 'te; h7tými ^- ÚTeňkamri ^- and L ¹ formed in' krdcích '362 and 370 - ¹ - ¹ S ^ subroutine.

This filling procedure consists of a number of more specific operations, designated MAX, PMAX, MIN and PMIN, which utilize processing of a set of basic data-values associated with said pixels. In a MAX operation, a given value is assigned to the pixels equal to the maximum base data value of eight pixels immediately adjacent to the pixel, and in a PMAX operation, the given data is assigned a new data value equal to the maximum base data value of four pixels. In a MIN-operation, another new data-value is assigned to that pixel, equal to the minimum base data-value of the eight pixels immediately adjacent to the pixel, and in the PMIN operation. is assigned a new value equal to the minimum of four pixels immediately adjacent to the pixel from the left, right, top, and bottom.

Figures 34a to 34e illustrate operations MAX, PMAX, MIN and PMIN. More specifically, Figure 34a shows a 7x7 array of numbers, and each number represents a pool pixel data value, wherein the position of the number in said array corresponds to the pool pixel address. So, for example, the data value for a pixel in the address (1,1) is 7, the data value for a pixel in the address (4,1) is 0, and the data value for the pixels in the address (4,2), (4,7) and (5.2) are 7, 0, respectively. 0.

Figure 34b shows the values after the MAX operation has been performed in the entire array of numbers shown in Figure 34a. Thus, for example, the data value (2,6) in Figure 34b is equal to 7, since one of the eight pixels adjacent to the pixel in Figure 34a is 7. Similarly, the value in the address (6,2) in Figure 34b is 7 since in the data file of Figure 34a one of the eight pixels adjacent to the pixel has a value. 7. Figure 34c shows the values obtained by the array of numbers shown in Figure 34a after the PMAX operation has been performed throughout this array. For example, the address values (6,3) and (6,4) in Figure 34c are equal to 7, since the addresses of both of these pixels are immediately adjacent to a pixel having a value of 7.

Figures 34d and 34e show the values obtained by the array of numbers shown in Figure 34a after a MIN-operation and a full-field operation have been performed over the entire array. PMIN-operation. For example, the value of the address (4,3) in Figure 34d is zero because one of the eight pixels adjacent to the address (4,3) in Figure 34a is zero, with the value in the address (4,2) in Figure 34e being zero because the pixel adjacent to this address from the right is zero.

Figure 35 shows a preferred filling process Rg. Referring to the figure, the procedure uses 14 separate operations performed on data values for pixel array 46, each of which is performed separately on each. a whole group of 46 pixels. The injections are consecutive in the following order: MAX ,. PMAX, PMAX, MAX, MAX, PMAX, PMAX, MIN, PMIN, PMIN, MIN, MIN, PMIN and PMIN. The default values for these operations are the I oro values of the pixels and the resulting data values after all 14 operations are denoted as 1 ^.

In effect, these operations fill in the gaps 436, the domed portions 442 'and the irregularities A40 in / on or adjacent the outer edge of the ring. 150. More specifically, Figures 33 and 36 show the same portion of the ring 150, the first figure showing pixels whose illumination values are

-1 - ^ - a — d-ru-h-— -picture — known.ug.e — p.ixe.l.ý, where the illumination value is 1 ^ · Differences between the two figures show the effects of the filling process shown in Figure 35. The difference between the two figures is in particular that the value of I1 pixels in the gaps 436, the domed portions 442,

Even in irregularities 440 and in the areas between the domed portions and the lines L, and L, it is equal to τ _nv , while the I _Q value of these 3 4 MAX y pixels is zero.

It will be appreciated that any other known technique can be used to produce the desired values of 1 µt * for the above pixels.

Upon completion of the padding process θ, the processor 64 uses a second reaming process Rg to produce a set of pixel illumination values that does not include the effects of light falling on a portion of the pixel array. 4, whose radius and center point are determined by the circle aligned during the decentration test, with the inner edge 150b of the ring 150. As will be described in greater detail below, this set of pixel illumination values subsequently aids in identifying defects in the inner part of the lens. radially inward from the inner edge of the ring 150.

The camouflage procedure used in this stage of the inspection procedure is very similar to the camouflage program R1 shown in Figures 19a. to. 19c and 20. The principle difference · between these two processes is that · the radius of the mask used in Postum _Rn is slightly smaller than the radius of the circle slícoy váného the inside edge of annulus 150 / while the radius of the mask used in procedure R is slightly larger than the radius of the circle aligned with the outer edge 150a of the ring 150.

Figure 37 shows a flow chart of a preferred masking process R _Q. The first step 446 of this program is to determine whether in steps 216 or 226 of the decentralization test at least three pixels have been discovered at the inner edge of the ring 150 or whether the ophthalmic lens has been found to be poorly decentrated. If it has been found in one of the two steps of the decentralization test described above that the lens is poorly decentrated, then the masking procedure Rg is terminated by itself in step 450.? CkH program Rg is not terminated in Step 45ú, proceeds to step 452 to obtain coordinates the center of the circle that was flush with the inner edge 150b of the ring 150 during the decentration test. These coordinates were determined and then stored in the processor memory during the process

A decentralization test, and these coordinates can be obtained by simply searching them in the processor's memory. After said center coordinates are obtained, a masking program is loaded in step 454. Referring to Figures 38a to 38c, this subroutine actually overlaps the pixel array 46 with a circular mask 456 whose center has the aforementioned center coordinates and has a diameter slightly smaller than the circle aligned with the inner edge 150b of the ring 150, then assigning the masking subroutine to individual pixels value More precisely Every pixel outside the mask is masked

.....- subroutine - assigns -value · I equal to value. Ιθ assigns a zero value to this pixel and to each pixel within the mask

More specifically, at step 452, the coordinates (x 1, y) of the aforementioned center point and the radius value that is selected to be slightly less than the radius value of the circle flush with the inner edge of the ring 150 are transferred to the masking subroutine. Then, in step 454, the subroutine creates a f-address file of all the pixels of the grouping 46 that are at a distance Γθ from said center point (x ^, y ^). Whereafter in step _________ ^_. _ ™. ^ £ 6O_proyě <.._ adre_s eny ^ y. "._. Všech._j> ixelů__seskupení a_ ^ 46 to determine if it the addresses in said file ίθ. If the pixel address is in that file, then at step 462. This pixel is assigned a zero value I _2, however, if the pixel address is not on the list, then in step 464 pixel přTřazena value ~ I ₂ s'h'o'ďn _About this pixel.

O

Any suitable oodorogram selected from a variety of known specific masking programs can be used in step 454 of program Rg.

Figure 38c shows an illuminated array of 46 pixels, with the illumination intensity of each pixel being equal to 1 ^ ·

Upon completion of this second masking procedure, another program zavedϊ, including a series of operations, is introduced to provide a set of pixel illumination values that clearly identifies the pixels that are in individual irregularities or defects in the inspected lens. More specifically, the purpose of these additional abutments is to provide a set of pixel illumination values that does not contain any phenomenon formed on the group 46 by background noise or any phenomenon formed on the group 46 by the normal or regular edges 150a and 150b of the ring 150. 39.

In step 466, an additional value of 1 is obtained for each pixel, more specifically, a value for each pixel is obtained by subtracting the value for said pixel from the value

Figures 40a, 40b and 40c show the pixels in a portion of the ring 162 that are illuminated at intensities of Iθ, I12, and _I2, respectively. ₁₃ , and it can be seen that the practical effect of step 466 is to subtract the image of Figure 40b from the image of Figure 40a to produce the image shown in Figure 40c.

Then, at step 470, an operation referred to as cleanup is performed to actually eliminate unwanted illuminated pixels. More specifically, the default values for the operations MAX, MIN, PMIN, and PMAX, which are performed, respectively, over the entire pixel array 46, are the values of the respective pixels, and these operations produce additional TcrafcroT-five-hed-hed labeled-as-note-notes. AND

Figure IUU illustrates illuminated pixel annulus pricamz light intensity equal to their value I, ^{and I, and} ^ is apparent when comparing Figures 40c and 40d, the objective cleanup is simply to eliminate various isolated pixels that, for a reason or in Figure 40c illuminated.

After the system 10 has already processed data according to the above-described R 1 -R 4 programs, a defect or defect analysis is performed, wherein Figures 41a and 41b show a flow chart of a preferred defect detection or analysis program. This analysis can be better understood with reference to Figure 42, which illustrates the pixels of a portion of the ring 150 illuminated with an intensity equal to their respective values of 1 ₁₄ ........ With reference to Figures 41a, 41b and 42 '', the first is the first. In step 472 and 474 of Figure 41a, a list of pixel addresses at the beginning and at the end of each horizontal series of successive illuminated pixels designated as the section being processed is constructed. More specifically, the processor 64 actually senses individual horizontal rows of pixels in the array 46, and during individual scans, each time a series of illuminated pixels is encountered, the first and last pixels of that series are recorded in the file fg. For individual isolated illuminated pixels, ie. pixels adjacent to the unlit pixels from the left and right, the address of these illuminated pixels is recorded as the first one, such as the ad-r-esa-last -ho "pixel in the processing section formed by said illuminated pixel.

More specifically, the processor does not actually capture the image on the pixel array,. but instead, the above exchanges compile the address list by examining the values stored in the processor memory for the grouping pixels 46.

After closing the file fg program R introduced subroutine at step 476 to create a separate file ^ 6a '''^ 6n P ^{ro' Ka} ždou area or group of contiguous illuminated pixels, or more precisely, for each area or group of contiguous pixels having high I value i Any suitable grouping subroutine can be used to perform this grouping. After these separate files are grouped, at step 480, the files are sorted for illuminated areas that are close to each other, such as those shown as 482 and 484 in Figure 42. This can be done, for example, by examining and determining whether any pixel of one the illuminated area lies within a given number of pixels, for example two or three, of any pixel in the other illuminated area. These nearby illuminated areas can in fact be considered as one illuminated area.

Upon completion of step 480, subroutines are run to calculate, in step 486, the area and center of gravity of the individual areas of the illuminated pixels and the bounding window of the areas. The whole?

Řadu · a number of known subroutines, and since these progame frames are well known, there is no need to describe them in detail here. . ..

Furthermore, the program R R determines the general position of each illuminated area. More precisely, in step 49Q, the center and radius addresses of the two circles aligned with the outer and inner edges 150a and 125a, respectively, are obtained. 150b of the ring 150. This data has been determined or detected during the post-run test and then stored in the processor memory, which can now be obtained by simply searching in said processor memory. Then, at step 492, the processor 64 determines whether said center of gravity of the individual areas of the illuminated pixels are located (i) within the central zone of said lens (an area radially within a circle aligned with the inner

The edge (p-rs-be-noed (or lil (in the outer zone of said lens, lobia-stented lenses between two rings collapsed on the inner and outer edges of said ring)).

A variety of known subroutines can be used to determine whether the center of gravity, the regions lie within the area defined by the first circle or between two generally concentric circles, and need not be described in detail here. Steps 490 and 492 are not necessary for operations of system 10 in a broad sense. The data associated with the above steps may be helpful in adjusting or elaborating the process or materials used to produce the lenses.

Upon completion of steps 490 and 492, the processor determines whether the size of each illuminated pixel area is large enough to be qualified as a 'defect' or defect for which the lens may be discarded. More specifically, at step 494, the size of each area of illuminated pixels is compared to a preselected size. If the illuminated area is smaller than a preselected size, the illuminated area cannot be considered sufficient to discard the lens. However, if the area of the illuminated pixels is greater than a preselected size, the illuminated area is qualified as a defect or defect that renders the lens unsuitable for use by the consumer. Said preselected size may be stored, for example, in a memory unit 70.

Furthermore, it is preferable to memorize the total number of defects found in each lens. This sum can be used to analyze the process and materials used to make the lenses.

In step 500, a display of illuminated pixel areas is created on the monitor 72 with those areas that are larger than the aforementioned limit size defined by the bounding window. Then, at step 5G2, the processor 54 checks to determine if any defect has actually been detected in said lens. If there is a defect in the lens, a lens reject signal is generated at step 504, which is then transmitted to the monitor 72 and to the printer.

76, and said lens may be removed from said system 10. However, if there is no defect in the lens, then the program R1 is simply terminated. The system 10 then displaces another lens by the illumination subsystem 14, whereby another light pulse penetrates through the next lens. The light that has passed through the lens is focused on the pixel array 46, followed by the above-described image processing procedure to determine that this 'additional' lens is acceptable for consumer use.

It is to be understood that the above-described embodiment of the method and system of the ophthalmic lens system of the present invention is illustrative only and is not intended to limit the scope of the invention as defined by the claims.

Claims (19)

An apparatus for supporting an ophthalmic lens, comprising a base member (106) and a cup (110) attached to the base member (106) and carrying an ophthalmic lens. a lens (84), said bowl (110) being substantially transparent and comprising a frustoconical side wall (110a) having a constant inclination and a hemispherically shaped bottom (110b) connected to the side wall (110a) extending from said side wall (110a) down and having a constant radius of curvature about 10% greater than a given radius of curvature of the ophthalmic lens (84). Device according to claim 1, characterized in that the cup (110) is symmetrical about the axis, the side wall (110a) of the cup (110) extending at an angle of about 20 ° to this axis and the thickness of the side wall (110a) of the cup (110) is less than about 0.254 ’mm. 3. Apparatus according to claim 2, characterized in that it is intended for supporting the eye lens (84) having a given diameter p'řič'e'mž ^- a bottom (ΊΊΌΈΠ dish ( "~ 1ΊΌ) has a diameter larger than the given diameter (84 ). Device according to claim 3, characterized in that the cup (110) has a depth greater than a given diameter. The device of claim 4, wherein said lens diameter (84) is approximately equal to 20 mm. by II The apparatus of claim 5, wherein the cup (110) has an upper circular portion having a diameter approximately equal to 22 mm. Device according to claim 6, characterized in that the cup (1-10) has a depth of approximately equal to 20 mm. Device according to claim 1, characterized in that the radius of curvature of the cup (110) is approximately equal to 11 mm. Device according to claim 1, characterized in that the cup (110) is made of polyvinyl chloride. An ophthalmic lens carrier comprising a base member (106) and a plurality of trays (110) attached to the base member (106), each of the trays (HO) being substantially transparent and comprising a truncated conical side wall (110a) having a constant inclination and a hemispherical bottom (110b) connected to and extending downwardly from the side wall (110a), wherein each of said bowls (110) houses one of a plurality of ophthalmic lenses (84) and ophthalmic lenses (84) have a uniform radius of curvature about 10% greater than a given radius of curvature of the ophthalmic lens (84). Carrier according to claim 10, characterized in that each ophthalmic lens (84) abuts the bottom (110b) of the cup (110) in which the ophthalmic lens (84) is received. Carrier according to claim 11, characterized in that each dish (110) comprises a liquid solution (112), wherein the eye lens (84) in each dish (110) is completely immersed in XII of this liquid solution (112). Carrier according to claim 11, characterized in that each cup (110) is symmetrical about an axis and the side wall (110a) of each cup (110) extends at an angle of 20 ° to this axis, wherein the thickness of the side wall (110 of each cup) 110) is less than about 0.254 mm. The carrier of claim 13, wherein the ophthalmic lenses (84) have the same given diameter, and the bottom (110b) of each dish (110) has a diameter greater than said given diameter of the ophthalmic lens (84). Carrier according to claim 14, characterized in that each dish (110) has a depth greater than a given diameter of the lens (84). 16. Apparatus for carrying ophthalmic lenses having a given radius of curvature, comprising a base member (106) and a plurality of trays (110) connected to the base member (106), each of the trays (110) being disposed in the base. substantially transparent and adapted to support the ophthalmic lens (84), and each of the trays (110) includes a frustoconical side wall (110a) having a stable side to the hem. -i-SF-ER-ieky t-va HCFC-base ^{- (-} 1 ~ 1Objspojené with the lateral wall (110a) extending from said side wall (110a) downward and having a constant radius of curvature about 10% larger than the said given radius of curvature of the lens (84). Apparatus according to claim 16, characterized in that each cup (110) is symmetrical about an axis and the side wall (110a) of each cup extends at an angle of about 20 ° relative to this axis, the thickness of the side wall (110a) of each cup (110) ) is less than about 0.254 mm. IV Apparatus according to claim 17, characterized in that the bottom (110b) of each cup (110) has a diameter greater than a given diameter of the ophthalmic lens (84) and each cup (110) has a depth greater than said given diameter. Apparatus according to claim 18. z .n. a. .č. e..n é. t. i .m., ..... wherein the plurality of trays (110) are arranged in a grouping of m x n trays (110) and the axes of the trays (110) are spaced apart by approximately 30 mm. The apparatus of claim 19, wherein each cup (110) comprises an upper annular portion having a diameter approximately equal to 22 mm, wherein the depth of each cup (110) is approximately equal to 22 mm and the radius of curvature of each cup (110) is approximately equal to 11 mm.